The Neotropics are one of the most biodiverse regions of the world, where
environmental dynamics, climate and geology resulted in a complex diversity of
fauna and flora. In such complex and heterogeneous environments, widely
distributed species require deep investigation about their biogeographic
history. The gray-breasted sabrewing hummingbird
Campylopterus
largipennis
is a species complex that occurs in forest and open
ecosystems of South America, including also high-altitude grasslands. It has
been recently split into four distinct species distributed in Amazonia
(rainforest) and Cerrado (savanna) biomes with boundaries marked by ecological
barriers. Here, we investigated the evolutionary dynamics of population lineages
within this neotropical taxon to elucidate its biogeographical history and
current lineage diversity. We used a reduced-representation sequencing approach
to perform fine-scale population genomic analyses of samples distributed
throughout Amazonia and Cerrado localities, representing all four recently
recognized species. We found a deep genetic structure separating species from
both biomes, and a more recent divergence between species within each biome and
from distinct habitats. The population dynamics through time was shown to be
concordant with known vicariant events, isolation by distance, and altitudinal
breaks, where the Amazon River and the Espinhaço Mountain Range worked as
important barriers associated to speciation.